A number of flexible plastic containers are well known in the art for storing and dispensing wine, soft drink syrup, dairy products, enteral feeding solutions, fruit juices, tea and coffee concentrates, puddings, cheese sauces, cleaning chemicals and many other flowable materials. The flexible containers described above typically have walls fabricated from polymeric films having either a monolayer or multiple layer structure. The particular polymers constituting the container film layers will often vary depending upon the type of material to be placed in the container.
In some instances, the film layers may additionally include an oxygen barrier material layer to prevent contact between such materials and oxygen or other gas sensitive contents. In some applications, the walls of the containers may be metallized, or coated with a metallic layer such as aluminum to prevent incursion of oxygen or other gases. A separate metallized enclosure may also encase the polymeric container.
These flexible polymeric containers generally have inlets and/or spouts for filling and dispensing the contents. The spout typically includes a flange which is sealed to an inside surface of one of the walls of the container. In most applications, the containers are then placed within a corrugated box. The spout extends through an opening provided in the box to dispense the contents. Such packaging systems are commonly referred to as “bag-in-box” or BIB. Bag-in-box systems have enjoyed wide success in a number of industries, most notably for use in containing and dispensing soft drink syrup and other liquid products. Prior art examples of such systems are shown in U.S. Pat. Nos. 4,286,636; 4,601,410; 5,647,511; 5,749,493; and 6,607,097 the entire disclosures of which are incorporated herein by reference.
The BIBs which are used to store and dispense soft drink syrup typically use fluid flow connectors to connect the containers to fountain dispensing machines. The fluid flow connectors generally have valves that remain closed until the connectors are attached to the spouts of the containers. Such valves include plungers that fit into the inlet of the fluid flow connector so as to regulate the flow of the soft drink syrup.
The plunger includes a member which is made of a hard plastic and an O-ring that is fitted to a distal end of the member. When the fluid flow connector is not attached to a BIB, the plunger is biased towards a closed position with the O-ring being pushed against the inlet of the fluid flow connector to provide a fluid tight seal. When the fluid flow connector is attached to a BIB, the spout of the BIB causes the plunger to be pushed away from the inlet thereby allowing fluid to flow through the inlet.
The O-rings which are used in BIB systems for dispensing soft drink syrup are made of ethylene propylene diene monomer or “EPDM”. It has been discovered by the applicant that, when the fluid flow connectors described above are attached to BIBs containing syrup for diet soft drinks, the O-rings swell. This swelling causes the fluid connectors to leak because the O-rings can no longer provide a fluid tight seal when the connectors are not connected to the containers. The leaking fluid flow connectors also lets air into the fountain dispensing machines, causing a loss of vacuum or suction and, in some cases, an adverse effect on the taste of the dispensed soft drinks. The swelling of the O-rings additionally creates another problem; the swollen O-rings decrease the flow rate through the fluid flow connectors when the connectors are attached to the spouts of containers and fluid is being dispensed from the containers.
For example, one study performed by the applicant showed that the EPDM O-ring used with existing fluid flow connectors swelled to 0.05 inches in a matter of weeks when it was exposed to diet soft drink syrup at elevated temperatures. This same swelling occurs over a matter of months for EPDM O-rings exposed to diet soft drink syrup at ambient temperatures. As a result of the swelling of the O-rings and the subsequent leakage of syrup, a large number of service calls are made by the syrup suppliers to replace the fluid connectors, plungers and/or the O-rings.
The above-described problems generate increased operating costs for the soft drink syrup suppliers who have to make additional service calls to soda fountain retailers to repair leaking fluid flow connectors. Moreover, fountain soda retailers incur increased operating costs because of the clean-up of leaked syrup caused by the leaking fluid connectors. The retailers also lose sales of diet fountain soda while waiting for the leaking fluid flow connectors to be repaired or from the connectors not being able to dispense the syrup properly.
The present invention is designed to provide advantages over the presently used system described above. A full discussion of the features and advantages of the present invention is deferred to the following detailed description, which proceeds with reference to the accompanying drawings.